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K Wilber

Publications and source records attributed to K Wilber.

7 recordsLinked to original sources
PubMed1998

FRA7G extends over a broad region: coincidence of human endogenous retroviral sequences (HERV-H) and small polydispersed circular DNAs (spcDNA) and fragile sites.

FRA7G is an aphidicolin-inducible common fragile site at human chromosomal band 7q31.2. This region is frequently altered in a number of different tumor types including prostate, breast, and ovarian cancer. It has also been hypothesized that this region contains an important tumor suppressor gene which is mutated during the development of these cancers or an oncogene which is amplified. We previously used a FISH-based approach to isolate YAC clones which spanned FRA7G. In this report, we describe the isolation and restriction endonuclease mapping of three overlapping P1 clones which cover FRA7G and the region frequently altered in the different cancers. FISH-based analysis of these clones reveals that aphidicolin-induced breakage in the FRA7G region occurs over a region of at least 300 Kb in length. We have also localized a previously sequenced BAC clone to this region. The sequence obtained from this clone reveals the presence of an endogenous retroviral sequence (HERV-H) in the midst of the FRA7G region as well as sequences with homology to small polydispersed circular DNAs (spcDNAs). Thus for the first two cloned common fragile sites, FRA7G and FRA3B, there is an association with both spcDNAs and hot-spots for viral integration.

Base Sequence↗
PubMed1998

A molecular cytogenetic analysis of 7q31 in prostate cancer.

Gains of chromosome 7 and alterations of the 7q-arm have been frequently observed in multiple cancers using various cytogenetic and molecular genetic techniques. Using PCR analysis of microsatellite markers, we have previously reported that allelic imbalance of 7q31 is common in prostate cancer and is associated with higher tumor grade and advanced pathological stage. In an effort to better understand the chromosome 7 alterations in prostate cancer, we undertook a molecular cytogenetic study of 25 prostate specimens using fluorescence in situ hybridization (FISH) with DNA probes for the chromosome 7 centromere and for 5 loci mapped to 7q31 (D7S523, D7S486, D7S522, D7S480, and D7S490) and 1 locus at 7q11.23 (ELN). Six tumors had no apparent anomaly for any chromosome 7 probe. Nine tumors showed apparent simple gain of a whole chromosome 7, whereas one tumor had apparent simple loss of a whole chromosome 7. Four tumors had gain of the chromosome 7 centromere and additional overrepresentation of the 7q-arm. One tumor had overrepresentation of 7q31 without any apparent anomaly of the chromosome 7 centromere, and one tumor had apparent loss of the chromosome 7 centromere with no apparent anomaly of the 7q-arm. Three tumors had gain of the chromosome 7 centromere and loss of the 7q31 region. Gain of 7q31 was strongly correlated with tumor Gleason score. Multiplex PCR studies of these specimens supported these FISH observations. Mutation screening and DNA sequencing of the MET gene, which is mapped to 7q31, revealed only the presence of simple sequence polymorphisms but no apparent acquired disease-associated mutations. FISH analysis of metaphases from an aphidicolin-induced, chromosome 7 only, somatic cell hybrid demonstrated that the DNA probe for D7S522 spans the common fragile site FRA7G at 7q31. Our data indicate that the 7q-arm, particularly the 7q31 region, is genetically unstable in prostate cancer, and some of the gene dosage differences observed may be due to fragility at FRA7G.

Chromosome Aberrations↗
PubMed1991

Competency requirements for policy gerontologists: what are the essentials?

"Policy gerontologists" are professionals knowledgeable about both public policy and aging. Through a survey of potential employers about the education of these specialists, the authors examined what is desired in terms of knowledge base, skill proficiencies, and behavioral characteristics. Although a solid knowledge of aging policies and the policymaking process are considered essential for policy gerontologists, respondents suggested that communication and political skills as well as the ability to take initiative and to follow through were also essential.

Aged↗
PubMedDate not supplied

Preserving antitrust.

The forces of organized medicine are arguing for changes in antitrust laws to allow exemptions for physicians. But, given the growing number of provider-sponsored health plans, are such changes necessary?

American Medical Association↗